I personally don't like religious names. I know far too many people who converted to a different religion or left religion completely. Clearly, there are many 'biblical' names that have somewhat lost a lot of their overt religious connection, like Tobias or Daniel, but I know three atheists named Christian, and one named Jesus, and there is a whole lot of room for resentment between the four of them. My SO has a name that's in the Bible, but is also a classic name that's not overt in it's religious connection. He was raised extremely religious but became an atheist in high school, and his name (think along the lines of Johnathan or David) has allowed flexibility from the religious childhood into his nonreligious adulthood.

Just wanted to put in the thought, your child might not want to follow the religion you want them to when they become independent adults, so if you insist on bestowing them with a "religious" name, you might want to keep in mind a name that can be versatile.

I come from two long lines of Catholics and my father's name is Daniel. I also have a cousin named Sarah. So yes, we do use Old Testament names. Old Testament names are everywhere, just as they were everywhere in the 1800s. They go in and out of fashion. You could always pair Tobias with a New Testament name, like TobiasAndrew or TobiasPeter.

I was a cradle Catholic, my dad was a cradle Catholic, my grandparents were, and so on back. In my family most of the guys especially (but a few girls too) have ot first names, Benjamin, Samuel, Jonathan, Isaac, Daniel, ect. There are very few who have nt names, less than half the amount that have ot names. Now the most common middle in my family are Joseph (dad, bro, gpa, cousins, ect) and Mary/Marie (gma, cousins, ect), so there you can really see the Catholic influence, but not so much in the first names. At least half of the first names aren't even Biblical or saint names. So if you're really concerned about making sure your son's name is "Catholic" enough I agree with the pp, use a new testament or saint middle. TobiasPeter is dashing, and could be seen as very Catholic since Peter was the first pope.

I grew up Catholic, not sure about names, but it might having something to do with the fact that as a Catholic, you follow the new testament, while Jews follow the old testament. So using an old testament name might appear to be Jewish for that reason.